The Institute of Electrical and Electronics Engineers (IEEE) wireless 802.11 standard is capable of supporting 8 spatial streams. The next generation WLAN, which may be referred to as Extreme High Throughput (EHT), is expected to support 16 streams.
According to known 802.11 Long Training Field (LTF) schemes, 16 LTF symbols are required to support channel estimation and Channel State Information (CSI) calculation for the 16 streams. When the 16 LTF symbols are required for the channel estimation, the length of the LTF symbols may be as long as 256 μs, which may result in substantial overhead.
Therefore, there is a need to develop certain mechanisms to support 16 stream channel estimation and to reduce the overhead at the same time.